An 18th.C. treadle lathe I made

[george wilson]

Metals can be turned freehand on this lathe. I mean using freehand wood lathe chisels. On modern lathes, I made a LOAD of spinning chucks from STEEL for the PGA trophies for many years. They were all curves,etc.,which you can't turn on a lathe which only does straight lines,of course.

What I did for some was to make an accurate drawing of the chuck, Then,I'd turn steps into the steel whose diameters would correspond to the drawing every 1/8". Last,I'd take wood lathe turning tools,mostly CARBON steel,and trim off the steps just with the freehand tools. This worked fine as I had the skill to pull it off. HSS lathe tools need sharpening less often. But,they did with carbon tools for thousands of years.

Later,I would rig up a primitive "tracer". I sawed the shape out of 1/8" black iron sheet and filed it smooth. I welded some 1" square steel bars to it,beyond where the actual shape was. This was SECURELY clamped to the rear of the bed. There was a flat there instead of a "V" way. I had "T" slots on the back of the cross slide,as some Asian lathes have (This was a 14" Sharp lathe). I mounted a steel "finger" in one of these T slots,so it could bear against the contoured pattern. The shape of this finger matched the shape of the turning tool EXACTLY. This was IMPORTANT. I used HSS cutters which I could easily grind to shape. In this case,tracer finger and cutter were 3/8" wide,and perfect semi circular in shape. The round shape left a quite smooth cut.

By the way,I had used leaded steel for these large turned shapes. It cut very well,and was perfectly strong enough for the job. These chucks were used only once fro the LARGE trophy,and several times for the "take home" trophies,which were reduced size copies of the large one.

Then,starting with a soldered together cylinder of steel,I'd just keep cutting material away. Finally,when I got down to near the actual required shape,I started at the HIGHEST point on the pattern and engage the power feed. I maintained contact with the pattern just by feel,being careful to NOT press against the pattern too hard with the tracer finger (no deflection wanted!) I'd come back to the high point and feed down hill in the other direction. It worked GREAT!! I got very accurate shapes. When I was about 1/32" from finishing the shape,I'd take it off the lathe,and PEEN the seams snugly together,eliminating the rougher bandsaw cuts. It worked perfectly. Then,I'd finish trimming the chuck down. Lastly,the chuck was heated up till the solder melted. Took LOTS of heat! The parts fell apart and the melted solder was wiped clean away with a cloth. And remaining could be quickly sanded away with wet or dry paper. At this stage the surface of the chuck was highly polished,so getting solder off was easy.

Now,these spinning chucks were SEGMENTED. The steel bar was cut into pie slices on the bandsaw. Then soft soldered together around a 2" diameter core which could be screwed onto the specified spindle thread of a manual spinning lathe. A groove cut into the lathe spindle of the end trapped the pie slices from falling out. A SECOND steel chuck was also needed,the exact same shape as the first one. It was solid steel,not segmented. This was to START the spinning: The solid chuck was only used to form the rounded BOTTOM of the metal being spun. Then,the half spun metal was put OVER the segmented end. BOTH ends of the project were then firmly trapped, and could not fly off. The upper part of the project was then spun,and the segmented chuck could be gotten out of the opening.

The aim was to make chucks that left little,or NO marks inside the projects where the seams in the segments were. Otherwise there was more work for the silversmiths getting rid of them. After I had made the first few chucks,and figured out how to do them better,NO segment marks were left on the metal. Even the first chuck,an 18th. C. style writing set for H.W. Bush,president,had hardly any segment lines.

One of these pie slices was REVERSE TAPERED. When you spun the metal and left an opening at the top,which was SMALLER in diameter than the chuck,you had to be able to EXTRACT the steel chuck. You would pull out the core,and the reverse tapered "key" would fall down inside the vessel,and could be pulled out. After that,ALL the keys could be extracted,leaving you with a hollow silver(or brass) shape. Usually a vase shape.

 

[george wilson]

The way the flywheel was made has been asked. I glued together 2 thick slabs of red oak,about 2 3/3" thick. They were oriented with their grains going 90º to each other,like the original. This to TRY to prevent the wheel from going oval when the humidity got high,or much lower.

The wheel was carefully cut with angled sides on the bandsaw. It was already a pretty heavy item to handle on the bandsaw,but I managed. I had no lathe in the shop that could finish turn this flywheel,and cut the grooves for the round drive belt. This is where it got interesting!

What I had to do AFTER adding the iron parts(the big X shaped piece that holds the axle,and the bolts and nuts that bolted the wheel together,was figure out how to cut those grooves to run true without a lathe to help.

I rigged up the flywheel in place on the lathe and slapped together a large hunk of wood I could lay a "V" shaped wood lathe chisel upon. I rigged up a 1/2 H.P. motor to turn the wheel IN PLACE,and CAREFULLY applied the V tool to it to cut the several grooves. It worked quite well,but was not the safest(or most dangerous!) thing I ever did.

They probably rigged up a similar way to do it originally,but without an electric motor!!

This has been a good,powerful lathe for the gunsmiths to turn out small items,like small screws and tumblers for flintlocks.

Since the gunsmiths moved to the foundry,which has a wooden lathe already(though not a SMIDGEN authentic,they gave the lathe to the Anderson Blacksmith shop where it now resides. The Gunsmith Shop recently went back to their original location. I'm sure they regret giving the lathe away. Their alternative is to HAND FILE out screws for metal and screws for wood. That takes forever! And,I am not there anymore to make them another.